以喹啉和双卤代烃为原料经季铵化反应合成了三种喹啉型双季铵盐酸化缓蚀剂:溴化1,4-二喹啉丁烷(Q-4-Q)、溴化1,6-二喹啉己烷(Q-6-Q)和溴化1,8-二喹啉辛烷(Q-8-Q),采用核磁共振氢谱对其结构进行表征。采用失重法,电化学方法和SEM等方法研究了三种产物在15% HCl溶液中对N80钢的缓蚀性能。结果表明,Q-8-Q的缓蚀性能最佳;双季铵盐Q-8-Q与肉桂醛(CA)最佳复配比为cQ-8-Q∶cCA=1∶1。在15%HCl,90 ℃条件下,6 mmol/L该复配缓蚀剂对N80钢片的缓蚀率达99.79%,缓蚀性能优良;缓蚀剂分子在N80钢片表面形成一层保护膜;该复配缓蚀剂能有效抑制酸液对N80钢表面的腐蚀,是一种以抑制阴极反应为主、属“负催化效应”作用机理的混合型缓蚀剂。

Three diquaternary ammonium salts as acidification corrosion inhibitors named 1,4-butane-bis-(quinoidine bromide) (Q-4-Q),1,6-hexane-bis-(quinoidine bromide) (Q-6-Q) and 1,8-octane-bis-(quinoidine bromide) (Q-8-Q) were prepared by quaternization of quinoline and alkyl halides. The synthesized compounds were characterized using HNMR spectroscopy. Weight loss method,electrochemical method and SEM were used to study the corrosion inhibition properties of those three products for N80 steel in 15% HCl solution. The results showed that Q-8-Q had the best inhibition efficiency,the best synergistic ratio for Q-8-Q and cinnamaldehyde (CA) was cQ-8-Q∶cCA＝1∶1. The inhibition efficiency for N80 steel in 15% HCl solution at 90 ℃ could reach 99.79% at the concentration of 6 mmol/L. A protective film was formed on the surface of N80 steel and confirmed by surface analysis experiments,the synergistic inhibitor was a mixed type inhibitor mainly to inhibit the cathodic reaction,which belonged to the “negative catalytic effect”.